refactor: start scripts as patches files, LED driver install in steps

patches/steamify-start.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+# Installed by Steamify CachyOS: run its newest release.
+# pipefail: a failed download must count as a failure, not an empty script.
+set -o pipefail
+if ! curl -fsSL --max-time 30 "@URL@" | bash; then
+    echo
+    echo "Couldn't download or run the wizard. Are you connected to the internet?"
+    echo
+    read -rp "Press Enter to close this window... " _
+    exit 1
+fi
+# Done: close the window after a countdown (Enter closes it right away).
+echo
+for (( i = 10; i > 0; i-- )); do
+    printf '\rClosing this window in %2d seconds (Enter to close now)... ' "$i"
+    read -rs -t 1 _ && break
+done
+echo